Is "Climate 365" really something officially sponsored by NASA ? It's hard to believe. Visiting that website I not only don't see the temperature chart shown in the Bishop's "Japanese Cool" article but I find a good deal of pathetic stuff (e.g. the "How you can save the world" section, which is not the only one which appear to have been written by someone who can neither spell nor write English.)

Funnily I have just posted elsewhere that the apparent need for there to be no deviation between the data sets is a cause for concern, well it is to me.

I real life, if all my usual suppliers presented the same "facts" I would immediately be off in search of confirmation from pastures anew until either confidence was gained or a different set of circumstances was found.

Competition between the data sets is needed, I think the benefits would be significant. It used to happen, Phil Jones was known to champion his CRU data, especially over GISS, critical of how they handled certain areas of the globe. This has now ceased to be the case and HadCRUT4 now shows a closer alignment.

The fact that the “big three” are always in agreement is a greater cause for concern than a source of solace.

"The land part of the combined data for the period before 2000 consists of GHCN (Global Historical Climatology Network) information provided by NCDC (the U.S.A.'s National Climatic Data Center), while that for the period after 2001 consists of CLIMAT messages archived at JMA. The oceanic part of the combined data consists of JMA's own long-term sea surface temperature analysis data, known as COBE-SST (see the articles in TCC News No.1 and this report)."

Being skeptical of the output of these graphs is beyond silly people. Everytime I hear or read the argument that temperatures of the entire globe can't be measured in centesimals of Kelvins I facepalm. Such ideas fly in the face of basic statistics. I think even Lubos Motl has touched on that point and explained very well, so I recommend you all to search his article about it and leave this silliness behind.

That chart looks misleading to me, compared with say this one using HadCRUT calculations for a global mean tempature: http://www.climate4you.com/images/HadCRUT3%20GlobalMonthlyTempSince1850%20WithSatellitePeriod.gif

Or this one using HadCRUT4 at Wood for Trees: http://www.woodfortrees.org/plot/hadcrut4gl

In each you will see a modest overlap of the monthly temperature ranges between the current decades and that of the 1940s. The plot you show above makes that look very unlikely. They are clearly not showing monthly means, but over some longer time period. Perhaps a year, perhaps a running mean of some kind. Whatever, it may well have been chosen for effect. The 'reality' (such an artifice as global mean temperature does deserve quotes here) is that the monthly temperatures show some overlap. Not so good for PR that.

I don't know about the rest of you but I agree that the period from 1910 to 1940 looks very similar to the period from 1970 to 2000, and yet only one of these periods is allegedly related to AGW/CC/EW.

The graph would look better with error bands on it, something on the order of +/- 0.2 C.

No amount of statistics can get a meaningful answer from insufficient data. The historical temperature records are largely derived from a relative handful of weather stations daily max / min records which themselves are not enough information to say much about the daily average temperatures. They are then adjusted in an attempt to compensate for station siting, missing records etc etc in a fairly arbitrary manner, then gridded to cover the vast areas of land where there is no data. All this done by people whose knowledge of statistics has been criticised by many.Sadly this is rife in acedemia; do a bad experiment, get a small number of dubious results and perform all sorts of statistical trickery on them to get the "right" answer.

Unfortunately in this case the general public is continually being sold the idea that "scientists" have been measuring "the average temperature of the earth" for centuries and that it is currently rising in an unprecedented manner. Part of this is graphs like the one shown, looks scary, actually shows a minor fluctuation on the basis of very little actual data.

I thought the main area of disagreement with regard to Global Warming was not whether the globe had warmed or not, most believe it has, but rather the causes, and the relative amount of warming attributed to each cause, of said warming. ignoratio elenchi me thinks.

Good guys or bad guys, there is no longer any excuse for posting a graph without providing a link to a simple file containing the data used by the person who created the graph. NASA should, and does, know better.

Now, looking at this graph, I could also be forgiven for thinking that someone at NASA is not as proud as they should be of data coming from satellites launched by NASA.

You may recall that Nerlich published a totally absurd article on CLimategate - see passim comments at CA http://climateaudit.org/2011/04/23/comments-on-mother-jones/ - in which her research was unequal to the challenge of determining which climate blogs were relevant in the story. SHe omitted the major climate blogs and instead studied a few very minor blogs that played no role in the Climategate story.

Steve, you want the next post down. I demand you retract this egregious comment, wrong and irrelevant and way beyond your skill set as a mining engineer. Only climate psychologists are able to unferstand the actions of skilled published climate psychologists. (Do I need to /sarc?)

I just took at quick look at the JMA COBE sea surface temperature data and there's nothing exceptional about it--which is good:http://bobtisdale.wordpress.com/2013/02/01/a-quick-look-at-the-jma-cobi-kobi-sea-surface-temperature-anomaly-data/

DMC yesterday - you are right, the most serious objection that many AGW sceptics have about cAGW concerns the extent to which last century's warming is due to CO2, and hence how much more warming we're likely to get for doubling of CO2.

That being said, sceptics also have some concerns about the reliability of the estimates we have of the amount of warming that happened in the last century. I think that few sceptics believe that there was NO warming in the 20th century - but you'll find plenty of sceptics who think that there has probably been a bit less than is portrayed in the average historical temperatures shown at the top of this post. This would be due to factors such as an increase in the amount of urban heat island effects over the century, and the inappropriate use of adjustments to historical sea-surface and land temperatures. There's a good post summarizing this kind of discussion at Climateaudit here.